Gear Wheel Method for Frequency Measurement: When a Lissajous figure contains a large number of loops, accurate counting becomes difficult. Figure 7.35 shows a test method that uses a modulated ring pattern in place of…
Speed Control of AC Commutator Motors: Speed control of ac commutator motors can be had either by varying the applied voltage or by movement of the brushes round the commutator. The former method makes use…
Visual Display Units (VDUs): Large arrays of characters can be built up using alphanumeric devices, already discussed, but the number of connections and the complexity of the drive-logic circuitry increase significantly, although large-scale integrated (LSI)…
Mathematical Formulation of Voltage Stability: Mathematical Formulation of Voltage Stability - The slower forms of voltage instability are normally analyzed as steady state problems using power flow simulation as the primary study method. "SnapÂshots" in…
What is Low Frequency Compensation? The coupling or blocking capacitor tilts the amplifier response for step input. In Fig. 16.28, if a high value of resistance Rd is added in series with RC which connects…
Directional Overcurrent Protection Principle: For the main bus-bars in the power stations, due to their importance in the operating conditions, it is required that the disconnection be without any delay in the case of faults.…
Relative Stability from the Nyquist Plot: Relative Stability from the Nyquist Plot - The considerations discussed above provide information about the absolute stability of the system, i.e., whether the system is stable or not. An…
Programmable Array Logic (PAL): We have seen that PLA device with a Programmable AND array and Programmable OR array. However, Programmable Array Logic (PAL) is a programmable logic device with a fixed OR array and…
Oscillator Amplitude Stabilization Circuit: Output Amplitude - For all of the Oscillator Amplitude Stabilization Circuit discussed, the output voltage amplitude is determined by the amplifier maximum output swing. The output waveform may also be distorted…
Bridge Controlled Error Detection: Bridge Controlled Error Detection - Whenever a bridge is unbalanced, a potential difference exists at its output terminal. The potential difference causes current to flow through the detector (say, a galvanometer)…
